RAPID METHOD FOR PRODUCTION OF CERIUM-CONTAINING OXIDE ORGANIC COLLOIDS

摘要

A rapid process for producing substantially non-polar cerium and iron containing oxide nanoparticle dispersions is disclosed. The nanoparticles of an acidic aqueous colloid are transferred to a substantially non-polar liquid comprising a carboxylic acid. The transfer is achieved by mixing the aqueous and substantially non-polar liquid comprising particular carboxylic acids, forming an emulsion, optionally adding a low-polarity or non-polar solvent, followed by a phase separation into a remnant polar solution phase and a substantially non- polar organic colloid phase. The organic colloid phase is then collected. The carboxylic acid causes rapid and substantially complete transfer of nanoparticles to the low polarity phase with phase separation of the substantially non-polar colloid from the remnant aqueous phase. It also provides excellent colloidal stability of the final substantially non-polar colloidal dispersion. Importantly, the carboxylic acid reduces the temperature necessary to achieve the rapid phase separation, while providing high extraction yield of nanoparticles into the substantially non- polar organic phase.